Pile fabric formation with varying height



Sept. 26, 1961 R. s. MacCAFFRAY, JR 3,001,338

PILE FABRIC FORMATION WITH VARYING HEIGHT Filed June 13, 1958 3Sheets-Sheet l ATTORN EYS 25 V 90 V (RI- g; TRECTIFIER INVENTOR zPfX a?MAC CAMP/1r 1x.

a A a y m. Q 6 R J mTAd a a ,g-vrrg u/ p 1951 R. s. MaOCAFFRAY, JR3,001,388

FILE FABRIC FORMATION WITH VARYING HEIGHT Filed June 13, 1958 3Sheets-Sheet 2 INVENTOR W J. mc arm; 16

TTORNEYS Sept. 26, 1961 R. s. MacCAFFRAY, JR 3,001,388

FILE FABRIC FORMATION WITH VARYING HEIGHT Filed June 15, 1958 3Sheets-Sheet 3 II III III INVENTOR mm". Maw; m

United States Patent fOfiice 3,001,388 Patented Sept. 26, 1.961

3,001,388 PILE FABRIC FORMATION WITH VARYING HEIGHT Rex S. MacCalfi-ay,Jr., Boiling Springs, Pa., assignor to C. H. Masland and Sons, Carlisle,Pa., a corporation of Pennsylvania Filed June 13, 1958, Ser. No. 741,810Claims. (Cl. 66--84) The present invention relates to the production ofhigh, low and intermediate pile in pile fabrics, and to the productionof high and low pile in warp knitted pile fabrics.

A purpose of the invention is to permit the production :of high, low andintermediate pile in pile fabrics formed of successive stitches, such astufted pile fabrics formed by a gang of needles passing through abacking, and warp knitted pile fabrics, by feeding the pile yarn to thepile fabric making machine selectively by a yarn feed which operates ata high speed or a speed less than the high speed, and during the stitchforming period selectively to maintain the operation of the yarn feed ateither the high speed or the speed less than the high speed for a longtime interval, an intermediate time interval, or a time interval lessthan the intermediate time interval.

A funther purpose is to subdivide at least some of the individualpattern elements (directly related to an individual stitch in thefabric) on the drum of the switch mechanism for controlling the pileheight in a pile fabric produced by successive stitching into incrementsof individual pattern elements less than a full pattern element for onestitch, maintaining the switch energized in some cases fora majorportion of the individual pattern elements, in some cases for anintermediate portion and in some cases for a minimum portion of anindividual pattern element which is less than the intermediate portion.

A further purpose is to subdivide the switch mechanism for controllingthe pile height on a pile fabric produced from successive stitches intoincrements less than a stitch in length, maintaining the switchenergized in some cases for a longer period, in some cases for anintermediate period and in some cases for a time less than theintermediate period.

A further purpose is to subdivide the contact making elements on apattern control pickup drum into contact elements less than a stitchperiod in length.

A further purpose is to drive a high speed feed roll or a low speed feedroll selectively for a short time interval to make high or low pile on awarp knitting machine, controlling one of a group of pile endsindividually.

Further purposes appear in the specification and in the claims.

In the drawings I have chosen to illustrate a few only of the numerousembodiments in which my invention may appear, selecting the forms shownfrom the standpoints. of convenience in illustration, satisfactoryoperation and clear demonstration of the principles involved.

FIGURE 1 is a diagrammatic perspective showing a warp knitting machineand associated electrical circuits, for producing a warp knitted pilefabric of three dilfereut heights according to the invention.

FIGURE 2 is a development of the pattern pickup drum according to theinvention.

FIGURE 3 is a diagrammatic sectional end elevation showing a tuftingmachine which may be used instead of the warp knitting machine in FIGURE1.

FIGURE 4 is a walewise section of a warp knitted pile fabric produced inaccordance with the invention.

FIGURE 5 is a longitudinal section of a tufted pile fabric produced inaccordance with the invention.

Describing in illustration but not in limitation and referring to thedrawings:

In the prior art high and low pile has been produced in tufted fabricwhere a gang of needles carry pile yarn ends through the backing fabricby electrically controlling the pattern on each stitch to determinewhether a high speed yarn feed roll or a lower speed yarn feed rollshall be effective to feed the individual yarn end during that stitch.This has involved the utilization of a pattern drum which for one stitchis conductive or makes contact throughout the stitch, and on anotherstitch is insulated or fails to make contact throughout the stitch. Theselective feed has been made effective by pulling back the previousstitch as well known in pattern tufting.

I have discovered that gradations in pile height can be produced bymodifying the electric contact mechanism so as to provide a long, ashort or an intermediate interval of yarn feed per stitch period.

I have also discovered that I can produce pile projections of two orthree or more heights by applying an electrical pattern control of thecharacter described, to the pile yarn ends fed to the pile yarn guidebar or guide bars of a warp knitting machine.

Considering now the form of FIGURE 1 in detail, I there illustrate aRaschel warp knitting machine of the character well known in the art,having a trick plate 20, needle bar 21, latch needles 22, plush pointbar 23 and plush points 24 of well known character, cooperating with asinker comb 25.

A swing bar 26 carries a series of transversely reciproeating orshoggable guide bars, comprising a guide bar 27 having eyes 28 whichreceive kniting yarn 30 from knitting yarn feed rolls 31 as well knownin the art. The swing bar also carries a guide bar 32 having eyes 33which receive a laid-in binding weft 34 from feed rolls '35. The swingbar also carries a guide bar 36 which has eyes 37 which carry face yarnends 38 from feed roll mechanism to be described. The swing bar alsocarries a guide bar 40 which carries eyes 41 which guide backing yarn 42from feed rolls 43.

The individual pile yarn ends of a set or group, each pass over aseparate set of feed rolls, of which a few of the many required acrossthe loom are illustrated.

It will be evident of course that the same set of feed roll mechanismscan take care of the feeding of a number of different pattern repeats ofyarn across the loom.

The feed rolls of an individual set comprise a roll 44 which is suitablykeyed on a shaft 45 and a roll 46 which is suitably keyed on a parallelshaft 47, the shafts being mounted on suitable bearings, not shown, andthe yarn desirably passing under one roll and over the other roll of theset to obtain firm frictional engagement with the roll surface. The twoshafts 45 and 47 are intergeared and driven at the same speed by gears48 and S0.

The selective speed drive of the rolls 44 and 46 is accomplishedpreferably by clutches. A main drive shaft 51 has keyed thereon a largesprocket 52' and a small sprocket 53. The sprockets are connected bychains 54 and 55 to a set of sprockets 56 and 57 which are coaxial withbut freely turn on the shafts 45 in nonengaging clutch position, thesprockets 56 and 57 being mounted on one of the normally free butelectromagnetically engaged cooperating clutch members ofelectromagnetic clutches 53 and 60, the opposite clutch elements beingkeyed on the shafts 45 as well known. The electromagnetic clutches maybe of any suitable character, an example being the Warner Electric BrakeCompany clutches.

The electromagnetic clutches have eleotromagnets which are grounded atone side internally, and have actu- The pattern control is accomplishedby an electrically 3 conducting drum 63, suitably of copper, which isturning at a uniform rate keyed on shaft 64, driven by a motor notshown.

Contact to ground is maintained on the drum by a ground contact finger65 mounted on an insulating mounting strip 66 and grounded at 67.

The drum has a plurality of contact paths 68 of which only a few areshown, and of which the arrangement is best seen in the development ofFIGURE 2. The arcuate travel of the drum 63 in a predetermined distancewhich will ordinarily be one stitch, is illustrated at 70, and providesa pattern control distance which may be selectively conducting as at 71,or nonconducting as at 72, or partially conducting as at 73 andpartially nonconducting as at 7 4, all in the distance of one stitch.

The manner of achieving the insulation, so as to prevent the contactfingers 75 on the insulating strip 66 from making contact at particularintervals, is not critical in the present invention, although a veryconvenient procedure is to place insulating tape patches, such aspressure sensitive tape patches 76 across the entire space of onelongitudinal path, and one stitch or a portion thereof as desired. Thismethod has the advantage that it permits ready change of pattern bysimply removing or relocating the insulating patches.

The energizing of the electric clutches is accomplished by leads 77connected to the individual contact fingers 75, which pass to oneterminal of relay coils 78, the opposite side of the relay coils beingconnected to lead 80 which is connected to one side, preferably the lowvoltage side 81, of rectifier 82 which is connected to an alternatingcurrent power source 83, at commercial voltage and frequency. The frameof the rectifier is grounded at 84. The opposite or high voltageterminal 85 of the rectifier is connected by lead 86 to two fixedcontacts 87 and 88 which are selectively connected by the movablecontact 90 of the relay either with fixed contact 91 which energizes orcauses to grip the high speed magnetic clutch, or with fixed contact 92which energizes or causes to grip the low speed magnetic clutch.

In operation, it will be evident that in accordance with well knownprocedure in a Raschel warp knitting machine, backing weft yarn is laidin, and following the procedure of my copending application Serial No.682,926, filed September 9, 1957, for Knitted Fabric Having Lay-in Weft,now abandoned, I lay in binding weft, wrap pile yarn around plush pointsand eventually bind the backing yarn, and the laid-in weft in stitchesof knitting chain as well known.

It will of course be evident that the same principle will apply with anyother warp knitting construction.

During the cycle of the warp knitting machine, depending upon the feed,the loops, when cast off by the plush points or when out on the plushpoints, will have a low tension if the high speed feed has been used, ora higher tension if the low speed feed has been used. Furthermore, ifthe high speed has been used for only a portion of the stitch durationand the low speed feed has been used for another portion of the stitchduration, the pile loop will be formed under a higher tension than ifthe high speed feed had been used throughout the stitch duration.Likewise, if the low speed feed were used throughout the stitchduration, the loop tension will be higher than if the high speed feedhad been used for some part of the stitch duration.

As a consequence, depending upon the relative proportion of the stitchperiod during which the individual pile yarn end is supplied by the highspeed feed compared to the portion of the stitch duration through whichthe individual pile yarn end is supplied by the low speed feed, the loopas cast off or as cut by the plush point will have a more. or lesspronounced tendency to pull back or pull down, and so. the final pilewill be of varying height.

This is made effective according to the present invention by thepresence and location or absence of the in- 4 sulating areas 76 in thepattern control path for the particular pile yarn end on the patterndrum 63. When the contact finger 75 encounters a contact area, and forso long as it encounters the contact area, it energizes the appropriaterelay 78 which closes fixed contact 87, movable contact and fixedcontact 91 to energize electromagnetic clutch 58 which includes the fastmoving sprocket, which then drives shafts 45 and 47 at the higher speedfor so long as the contact finger 75 makes contact.

As soon as the contact finger 75 ceases to make contact (and this mayhappen at the end of the stitch or of a subsequent stitch, or once orseveral times during the stitch), the relay 78 deenergizes and contacts88, 90 and 92 close, which energize electromagnetic clutch 60 whichincludes the slow moving sprocket drive for the corresponding shafts 45and 47.

Actually in the preferred embodiment there will be the following threeconditions encountered:

(1) In the first condition, the entire stitch length of a particularpattern path on the drum 63 is conducting and therefore the fast feedoperates for the entire time of the stitch, and a high loop is produced.

(2) In the second case, a portion of the stitch length on the patternpath is conducting and a portion is nonconducting, so that there will bea part of the stitch time during which the fast feed operates and a partof the stitch time during which the slow feed operates. This produces apile projection of intermediate height.

(3) In the third case, the entire stitch length of the pattern path isnonconducting and the entire feed of yarn to the stitch is at the slowspeed, producing a pile projection which is low.

In some cases, however, it will be evident that advantage can beobtained by applying the invention to a warp knitting machine even whereonly two conditions prevail, for example, either a conducting conditionor a nonconducting condition through the stitch length of the patternpath.

The result in accordance with the present invention is the production ofa warp knitted pile fabric of FIGURE 4 which has knitting chain 93 whichgrips laid-in backing weft 94 and binding weft 95 to form a'tuft bindfor pile yarn 96 which exists in this case in four heights, high pileprojections 97, secondary high pile projections 98, lower pileprojections 100, and still lower pile projections 101. While these pileprojections are shown as uncut loops, there are dot-and-dash linesshowing the tufts to illustrate that the loops may be out if desired.

The principles of the invention are applicable to other forms ofstitched pile fabric manufacture, for example as illustrated in thetufted pile fabric of FIGURE 3.

In this construction it will be understood that all the features ofFIGURE 1 apply except the detail of the Warp knitting machine, which issubstituted by the tufting machine of FIGURE 3. Backing fabric 102 suchas burlap or Osnaburg is drawn from a suitable source over guide rolls103 and fed across a needle plate 104 by a take-up mechanism 105 as wellknown, the backing fabric being held down by a guiding foot 106.

A needle bar 107 carries a gang of needles 108 arranged in line, theneedle bar being reciprocated by an eccentric 110 which is acting on aneccentric strap 111 which is pivotally connected at 112 withreciprocating rod 113 which is guided at 114 on the frame. Thepile yarn38 is taken from the feed mechanism as shown in FIGURE 1 through guidingeyes 115 and 116 on the frame and a guiding eye 117 on the needle bar tothe eyes 118 on the needles 108.

After the loops are formed, they are engaged by synchronized loopers 120which are oscillated as well known on a looper shaft 121. The operationin the device of FIGURE 3 is the same as that of FIGURE 1 except thatthe pull-back action which produces variant loop heights,

depending upon the extent of feed during the "stitch, is

made effective on the previous loops which have been formed in the lastprevious stitch. The resulting product as shown in FIGURE 5 comprises abacking fabric 122, which has high loops 123, intermediate loops 124 andlow loops 125 of suitable pile yarn 38. The loops may be cut as shown.

It will be evident that the high loops are formed when contact is madeduring all or a large part of the stitch distance on the pattern drum63, the intermediate loops are made when contact occurs during a lesserbut appreciable part of the stitch length of the contact path, and thelow loops result when the insulation is present for all or a substantialpart of the stitch length of the contact path. Of course it will beevident that the device can be arranged so that either the contact onthe pattern drum causes the relay to energize the fast clutch or theslow clutch, and if the reversal is accomplished, then the presence ofthe contact throughout the stitch length will produce a low pileprojection rather than a high pile projection in either of the forms.

It will be evident of course that it may be convenient in some cases touse incremental insulation strips of a standard size, and to apply none,one, two or several such strips to the contact path as desired. Wherethis is done it will of course be understood that it is immaterialwhether the contact areas in the stitch length are adjoining or spaced.

It will be evident that the feed rolls of the difierent sets Will extendacross the machine, and be duplicated where the width of the machine isso great that the feed roll length becomes excessive. There willnormally be a pattern repeat length widthwise of the machine which willbe uniform. For example, if the pattern repeat length is pile yarn ends,then the first, the 21st, the 41st and the 61st ends etc. will becarried over the same feed roll set, and the 2nd, 22nd, 42nd and 62ndetc. pile yarn ends will be carried over another feed roll set, and the3rd, 23rd, 43rd, 63rd etc. pile yarn ends will be carried over anotherfeed roll set and so on. Of course, if two ends in the repeat behavealike throughout, for example the first and the 19th, then they can befed by the same feed roll set.

In view of my invention and disclosure variations and modifications tomeet individual whim or particular need will doubtless become evident toothers skilled in the art to obtain all or part of the benefits of myinvention without copying the structure and method shown, and Itherefore, claim all such insofar as they fall within the reasonablespirit and scope of my claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A mechanism for forming pile loops of difierent heights from theyarns of a pile warp comprising a united series of aligned, cyclicallymoved pile loop formers receiving said yarns and adapted each to formone of a row of pile loops with each cycle of its movement, a pluralityof variable speed yarn feeding mechanisms for feeding yarn to said loopformers, a high speed and a low speed drive means, a pair ofelectrically operable clutches for each yarn feeding mechanism adaptedto selectively engage the associated feeding mechanism with said high orlow speed drive, a circuit to energize each said clutch, a relayconnected to selectively energize the pair of circuits to each said pairof clutches accordingly as said relay is actuated or not, an actuatingcircuit for each said relay and timing means for selectively closingsaid actuating circuits for various intervals all of which are shorterthan the cycle period of said loop formers.

2. A mechanism of claim 1, in which said united series of aligned,cyclically moved pile loop formers comprise the pile loop formers of aknitting machine.

3. A mechanism of claim 1, in which said united series of aligned,cyclically moved pile loop formers comprise the needles of a tuftingmachine.

4. A mechanism of claim 1, in which said timing means closes saidactuating circuits selectively for long, intermediate and short timesall within the cyclic period of said loop formers.

5. A device of claim 1, in which said timing means comprises patterndrum means which advances a predetermined distance for each cycle periodof said loop formers and which includes contact means which isrelatively long, short and intermediate in contact duration as the casemay be, and contact fingers which contact said pattern drum means.

References Cited in the file of this patent UNITED STATES PATENTS510,958 Cond Dec. 19, 1893 510,959 Cond Dec. 19, 1893 2,781,007 ThompsonFeb. 12, 1957 2,782,905 Smith Feb. 26, 1957 2,810,471 Shattuck Oct. 22,1957 2,853,034 Crawford Sept. 24, 1958 2,862,465 Card Dec. 2, 19582,876,183 Parlin Mar. 3, 1959 2,932,181 MacCallray Apr. 12, 19602,935,037 Card May 3, 1960 FOREIGN PATENTS 735,019 Great Britain Aug.10, 1955

